This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Standard of Care Chemotherapy With or Without Stereotactic Body Radiation Therapy for Oligometastatic Pancreatic Cancer (NCT04975516), a randomized phase 2 study. The primary outcome is Progression Free Survival.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04975516 |
| Phase | Phase 2 |
| Condition | Metastatic Pancreatic Adenocarcinoma, Stage IV Pancreatic Cancer AJCC v8, Recurrent Pancreatic Adenocarcinoma |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Mayo Clinic |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerned patients with pancreatic cancer that had spread to a limited number of places in the body, described as oligometastatic pancreatic adenocarcinoma. The registry conditions also include metastatic, recurrent, and stage IV pancreatic cancer. The record does not provide further eligibility criteria or a detailed description of the enrolled population.
Intervention
One group was assigned stereotactic body radiation therapy (SBRT) together with standard-of-care chemotherapy. The arm description says SBRT was delivered once daily or every other day for 5 fractions, with chemotherapy given according to standard of care. The registry does not report which chemotherapy regimens were used.
Comparator
The comparison group received standard-of-care chemotherapy without SBRT. The record does not describe a particular chemotherapy regimen, nor does it provide details about how treatment choices were made within standard care.
Primary question
The primary endpoint was progression-free survival: the time from randomization to the first of disease progression or death from any cause, assessed up to 2 years. The clinical question was whether adding SBRT to chemotherapy was associated with a different course of progression-free survival than chemotherapy alone. The registry does not report an outcome estimate or a between-group comparison, so this question cannot be answered from the posted results.
3. Trial Design
This was a randomized, parallel-group phase 2 trial with no masking. The registry lists an enrollment of 2 and identifies Mayo Clinic as the sponsor. The record gives a start date of 2023-07-18 and a primary completion date of 2025-11-15. Its status is terminated. These record details describe the trial's listed design and conduct dates; they do not establish why the trial was terminated.
The planned comparison was standard-of-care chemotherapy with SBRT versus standard-of-care chemotherapy alone. The SBRT arm description specifies treatment once daily or every other day for 5 fractions. The registry lists chemotherapy and SBRT as interventions, along with computed tomography, magnetic resonance imaging, biospecimen collection, and questionnaire administration. It does not give a detailed schedule for imaging, biospecimen collection, or questionnaires, nor does it specify which chemotherapy drugs were administered.
Randomization is listed, but details such as the allocation procedure, allocation concealment, stratification factors, and planned group sizes are not reported in the registry record. No masking was used. The record says only 1 patient received treatment and was included in the analysis population. Because outcome information for that patient is withheld to preserve anonymity, the posted results cannot show how the randomized comparison turned out. The registry also lists no outcome analyses. Termination, limited treatment exposure, and the absence of a reported outcome estimate sharply limit what can be learned about comparative effects.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Group I (SBRT, Chemotherapy) | Group II (Chemotherapy) |
|---|---|---|
| STARTED | 1 | 1 |
| COMPLETED | 1 | 0 |
| NOT COMPLETED | 0 | 1 |
Reasons for not completing this period:
| Reason | Group I (SBRT, Chemotherapy) | Group II (Chemotherapy) |
|---|---|---|
| Patient withdrawal prior to beginning treatment | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: Since only 1 patient received treatment and is included in the analysis population, their outcome information will not be reported to preserve anonymity.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Since only 1 patient received treatment and is included in the analysis population, their demographic information will not be reported to preserve anonymity.
| Characteristic | Unit | Group I (SBRT, Chemotherapy) | Group II (Chemotherapy) | Total |
|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | |
| Sex: Female, Male: Female | — | — | — | |
| Sex: Female, Male: Male | — | — | — | |
| Ethnicity (NIH/OMB): Hispanic or Latino | — | — | — | |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | — | — | — | |
| Ethnicity (NIH/OMB): Unknown or Not Reported | — | — | — | |
| Race (NIH/OMB): American Indian or Alaska Native | — | — | — | |
| Race (NIH/OMB): Asian | — | — | — | |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | — | — | — | |
| Race (NIH/OMB): Black or African American | — | — | — | |
| Race (NIH/OMB): White | — | — | — | |
| Race (NIH/OMB): More than one race | — | — | — | |
| Race (NIH/OMB): Unknown or Not Reported | — | — | — | |
| Region of Enrollment: United States | participants | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as Progression Free Survival, measured over Time from randomization to the first of either disease progression or death from any cause, assessed up to 2 years.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
Progression-free survival (PFS) measures the time from randomization until the first of disease progression or death from any cause. In this trial, progression was to be determined using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. The registry says assessment would occur at each enrolling site, with no central review planned, and gives an assessment period of up to 2 years.
As a general statistical concept, a time-to-event endpoint preserves information about when an event occurs, rather than recording only whether it happened by a single point in time. It can therefore describe both the occurrence and timing of progression or death. That interpretation depends on how events, follow-up, and censoring are defined and recorded; those detailed rules are not reported in the registry record.
The PFS definition combines progression and death, so either event qualifies as an endpoint event. The record does not report a PFS estimate, an event count, a hazard ratio, a confidence interval, or a comparison between groups. It explains that the outcome information for the 1 patient in the analysis population is not reported to preserve anonymity. Consequently, the endpoint is described, but its observed result cannot be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the intended comparison and defines the primary endpoint, but it does not provide a result that quantifies the effect of adding SBRT. It reports that only 1 patient received treatment and was included in the analysis population, and that the patient's outcome information is withheld to preserve anonymity. No estimate of progression-free survival or comparison between the two treatment groups is available in the posted results. There is therefore no basis in this record for describing the direction, size, or precision of a treatment difference.
The registry lists enrollment of 2, but this should not be mistaken for an outcome-analysis denominator. The stated analysis population and the reported reason for withholding results are the relevant context for interpreting the absent PFS information. The registry lists 0 analyses. It does not report an effect estimate, a confidence interval, or a test statistic for the primary endpoint. A confidence interval, in general, expresses the range of effect values compatible with the data and statistical assumptions; without a reported estimate and interval, precision cannot be evaluated.
The adverse-event record lists 0 participants at risk, 0 participants affected, and 0 deaths for each group, with no serious adverse-event terms listed. These entries do not provide a basis for concluding that treatment caused no adverse events. In particular, the registry separately reports that only 1 patient received treatment and that the outcome information is not reported to preserve anonymity; the adverse-event rows do not establish an interpretable exposed denominator or a comparative safety estimate. The entries should be read as registry entries, not as proof of absence of harm.
The trial status is terminated. The registry gives a primary completion date of 2025-11-15 but does not report why the trial ended, whether recruitment stopped early, or what operational circumstances led to termination. Those reasons should not be inferred from the status alone. The posted information is therefore descriptive of the trial record and its limited reported results, rather than evidence that supports a comparative efficacy or safety conclusion.
Planning assumptions associated with sample-size illustrations specify a two-sided significance level of 0.05, equal allocation, and a normal approximation. They describe planning calculations, not the trial's own design or observed power. The record does not report a single observed effect estimate from which to judge a planned detectable effect against an observed result. Any such illustration cannot substitute for clinical outcome data or repair the absence of a reported comparison.
9. Statistical Methods Explained
What does randomization contribute?
Randomization assigns participants to treatment groups using a chance-based process. In general, this can help balance both measured and unmeasured prognostic characteristics across groups, making a between-group comparison less vulnerable to selection differences. It does not guarantee balance in every trial, particularly when few participants are treated. Here, the registry identifies the design as randomized and parallel, but the record does not report the allocation procedure, concealment approach, or any stratification factors. The posted record also does not provide outcome estimates that would allow a randomized comparison to be examined.
How should a time-to-event outcome be understood?
Progression-free survival records the time from randomization to the first of progression or death from any cause. This differs from a simple proportion because the time until an event is part of the outcome. In general, time-to-event analyses can account for participants whose event has not been observed by the end of their available follow-up through censoring. Censoring does not mean that an event occurred; it indicates that the event time is not known beyond a particular point. The registry record does not describe censoring rules, follow-up completeness, or the analysis method for PFS. No time-to-event estimate is reported.
What does the progression assessment involve?
The registry specifies RECIST 1.1 criteria for determining disease progression, with documentation at each enrolling site and no central review planned. As a general matter, common criteria can make assessments more consistent by giving sites a shared framework. Site assessment without central review can leave assessment dependent on local documentation and interpretation. The record does not provide the imaging schedule, adjudication procedures, or details about how ambiguous assessments would be handled. Those details should not be assumed.
What can be inferred from the analysis information?
The registry lists 0 analyses and does not report a PFS effect estimate, confidence interval, or statistical test. It also does not report a statistical analysis plan, including whether the planned comparison would use a particular survival model, adjust for covariates, or apply a specified test. Those methods are not recoverable from the endpoint definition alone. In general, a confidence interval describes uncertainty around an estimated effect under the model and assumptions used. A test result addresses compatibility with a specified null hypothesis, but is not itself a measure of effect size or clinical importance. Neither type of result is available for the primary comparison.
What do the planning assumptions mean?
The record describes sample-size illustrations using a two-sided significance level of 0.05, equal allocation, and a normal approximation. It says that the effect to detect is expressed as a stated fraction of the observed effect; for time-to-event outcomes, the illustration concerns a total number of events, while other outcomes use participants per arm. These are planning conventions, not reported features of the trial's own design. The registry does not report the trial's sample-size justification. Because no observed primary effect is available in the registry, the planning assumptions cannot be used to establish how well the trial could detect an effect or to infer an outcome. Planning calculations are not observed power.
Why does over-dispersion matter in general?
Over-dispersion is a general issue for count outcomes when variability is greater than a statistical model assumes. If unaccounted for, uncertainty can be understated, making intervals too narrow and tests too optimistic. It is relevant when a count-based analysis uses a model that assumes a particular variance structure. The registry record does not identify a count-based primary analysis or report a statistical model, so over-dispersion cannot be evaluated as a trial-specific issue. This general concept does not alter the central limitation: the posted record contains no reported PFS comparison.
Overall, the registry gives a trial design, an endpoint definition, and some planning assumptions, but not the analysis details or outcome data needed to reproduce or assess a treatment-effect estimate. No analysis method should be attributed to the trial beyond what the record explicitly states.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists progression-free survival as the primary outcome and identifies confirmed response rate, overall survival, and incidence of adverse events as secondary outcomes. It reports 4 outcome measures, but provides no analyses. The record does not describe a testing hierarchy, multiplicity adjustment, or a strategy for controlling the chance of false-positive findings across outcomes or time points. It is therefore not possible to determine how multiple comparisons were intended to be interpreted.
Multiplicity is a general concern when several outcomes, time points, or subgroup comparisons are tested. Repeated testing can increase the chance that at least one apparently notable result arises by chance. A prespecified hierarchy or adjustment can address that issue, but neither is reported in the registry record. There are no reported p-values or outcome estimates for which an adjustment could be assessed.
The primary PFS outcome information is withheld because only 1 patient received treatment and was included in the analysis population. This is a privacy-based non-reporting explanation in the record; it should not be conflated with a documented pattern of missing follow-up measurements. The registry does not report missing-data counts, reasons for missingness, imputation methods, censoring rules, or sensitivity analyses. It also does not report an analysis population definition beyond the statement about the 1 patient. Accordingly, the effects of missing data or exclusions cannot be evaluated.
The registry's listed adverse-event values are 0 for participants at risk, participants affected, and deaths in each group, and it lists no serious adverse-event terms. Given the reported treatment and analysis context, those entries do not establish complete safety follow-up or a comparison of adverse-event risk. The record does not provide further denominators or an explanation of how adverse-event reporting relates to the single treated patient.
11. What the Result Does, and Does Not, Mean
The record shows that a randomized phase 2 comparison of chemotherapy with or without SBRT was registered for oligometastatic pancreatic cancer, and that PFS was the primary endpoint. It also states that only 1 patient received treatment and was included in the analysis population. The patient's outcome information is not reported to preserve anonymity. These registry entries describe the available evidence; they do not reveal whether either group had better or worse PFS.
No effect estimate, confidence interval, or formal comparison is reported. This means neither the size nor the precision of a difference can be evaluated. It also means that the record cannot establish whether an apparent difference would be compatible with no difference or with a range of potentially different effects. Such conclusions require outcome data and an analysis, neither of which is available in the registry record.
The listed adverse-event entries should not be interpreted as proof that no harms occurred. The registry reports 0 participants at risk, 0 affected, and 0 deaths in each group, while also describing limited treatment exposure and withholding the individual outcome information. Without an interpretable account of the exposed population and complete safety follow-up, those entries do not support a comparative safety conclusion.
In general, a terminated trial can still provide useful evidence if its observed data and analyses are reported. In this record, however, termination is not accompanied by an explanation, and the primary outcome is not reported. The result therefore cannot be used to conclude that SBRT plus chemotherapy improves, worsens, or leaves unchanged progression-free survival, response, overall survival, or adverse events. It also cannot establish that the approaches are equivalent. The appropriate interpretation is that the registry documents the intended study and limited reported results, while leaving the clinical comparison unresolved.
12. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between a planned randomized comparison and an interpretable result. Randomization is a valuable design feature in general, but a randomized label does not itself provide evidence about the treatment contrast. Estimation requires observed outcomes and a reported analysis. The registry record describes the intended groups and PFS endpoint but withholds the outcome information for the 1 patient in the analysis population.
The record also highlights the importance of separating enrollment, treatment exposure, and analysis populations. It lists enrollment of 2, while stating that only 1 patient received treatment and was included in the analysis population. Those are not interchangeable descriptions of the evidence available for an outcome estimate. Without reported group-level outcome data and denominators, the comparison cannot be reconstructed or its precision assessed.
Planning assumptions are useful for illustrating how a future study might be designed, but they do not replace observed outcomes. The record's assumptions about significance level, allocation, and approximation are not the trial's own reported statistical plan, and they are not evidence of observed power. This distinction is especially important when no effect estimate is reported from which to judge a planning target.
Finally, the record demonstrates why outcome reporting and transparent analysis plans matter. The endpoint definition and criteria are useful, but the missing effect estimate, confidence interval, analysis methods, and termination explanation sharply restrict statistical interpretation. The trial is a record of a planned comparison, not a reported comparative finding.
13. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation is that the primary outcome information is not reported. The registry explains that only 1 patient received treatment and was included in the analysis population, and that their outcome information is withheld to preserve anonymity. As a result, there is no reported PFS estimate or comparison between the randomized groups. The record lists enrollment of 2, but does not provide an outcome denominator for each group.
The record marks the trial as terminated but does not state the reason. It does not describe recruitment progress, the circumstances of termination, or whether any planned analyses were completed. The primary completion date is listed as 2025-11-15, but the record does not explain how that date relates to termination or data availability.
Several design and analysis details are not reported in the registry record, including allocation procedures, sample-size justification, the statistical analysis plan, censoring rules, missing-data handling, and any interim analysis. The record also does not report chemotherapy regimens or detailed schedules for the listed assessments. These gaps prevent evaluation of the planned analysis and of how the endpoint was measured beyond the stated RECIST 1.1 criteria and site-level documentation.
The safety entries list 0 participants at risk, 0 affected, and 0 deaths in each group, with no serious adverse-event terms. In the context of limited treatment exposure and withheld outcome information, these entries do not provide a clear basis for estimating or comparing safety. The record therefore has substantial limitations for both efficacy and safety interpretation.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Standard of Care Chemotherapy With or Without Stereotactic Body Radiation Therapy for Oligometastatic Pancreatic Cancer — NCT04975516.
- Registry record last updated 2026-06-18; status last verified 2026-05.
- Results first posted 2026-06-18.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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17. Record Summary
This terminated randomized, parallel-group phase 2 trial was sponsored by Mayo Clinic. It compared standard-of-care chemotherapy plus SBRT with standard-of-care chemotherapy alone for oligometastatic pancreatic cancer. The registry lists enrollment of 2, a start date of 2023-07-18, and a primary completion date of 2025-11-15.
The primary endpoint was progression-free survival from randomization to disease progression or death from any cause, assessed up to 2 years using RECIST 1.1 criteria at each enrolling site, with no central review planned. Only 1 patient received treatment and was included in the analysis population; the outcome information is not reported to preserve anonymity. The registry lists no analyses and no primary outcome estimate. Its adverse-event rows contain zero entries for participants at risk, affected participants, and deaths in both groups. These data do not support a comparative conclusion about efficacy or safety.